/* GNU gettext - internationalization aids
   Copyright (C) 1997-2025 Free Software Foundation, Inc.

   This file was written by Peter Miller <millerp@canb.auug.org.au>

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

#include <config.h>

#include <limits.h>
#include <locale.h>
#include <stdio.h>
#include <stdlib.h>

#include <textstyle.h>

#include <error.h>
#include "options.h"
#include "noreturn.h"
#include "closeout.h"
#include "dir-list.h"
#include "str-list.h"
#include "file-list.h"
#include "error-progname.h"
#include "progname.h"
#include "relocatable.h"
#include "basename-lgpl.h"
#include "message.h"
#include "read-catalog.h"
#include "read-po.h"
#include "read-properties.h"
#include "read-stringtable.h"
#include "write-catalog.h"
#include "write-po.h"
#include "write-properties.h"
#include "write-stringtable.h"
#include "xerror-handler.h"
#include "msgl-cat.h"
#include "propername.h"
#include "gettext.h"


/* A convenience macro.  I don't like writing gettext() every time.  */
#define _(str) gettext (str)


/* Force output of PO file even if empty.  */
static int force_po;

/* Target encoding.  */
static const char *to_code;


/* Forward declaration of local functions.  */
_GL_NORETURN_FUNC static void usage (int status);


int
main (int argc, char *argv[])
{
  int cnt;
  bool do_help = false;
  bool do_version = false;
  msgdomain_list_ty *result;
  catalog_input_format_ty input_syntax = &input_format_po;
  catalog_output_format_ty output_syntax = &output_format_po;
  bool sort_by_msgid = false;
  bool sort_by_filepos = false;
  const char *files_from = NULL;
  string_list_ty *file_list;
  char *output_file = NULL;

  /* Set program name for messages.  */
  set_program_name (argv[0]);
  error_print_progname = maybe_print_progname;
  gram_max_allowed_errors = 20;

  /* Set locale via LC_ALL.  */
  setlocale (LC_ALL, "");

  /* Set the text message domain.  */
  bindtextdomain (PACKAGE, relocate (LOCALEDIR));
  bindtextdomain ("gnulib", relocate (GNULIB_LOCALEDIR));
  bindtextdomain ("bison-runtime", relocate (BISON_LOCALEDIR));
  textdomain (PACKAGE);

  /* Ensure that write errors on stdout are detected.  */
  atexit (close_stdout);

  /* Set default values for variables.  */
  more_than = -1;
  less_than = -1;
  use_first = false;

  /* Parse command line options.  */
  BEGIN_ALLOW_OMITTING_FIELD_INITIALIZERS
  static const struct program_option options[] =
  {
    { "add-location",       CHAR_MAX + 'n', optional_argument },
    { NULL,                 'n',            no_argument       },
    { "color",              CHAR_MAX + 5,   optional_argument },
    { "directory",          'D',            required_argument },
    { "escape",             'E',            no_argument       },
    { "files-from",         'f',            required_argument },
    { "force-po",           0,              no_argument,      &force_po, 1 },
    { "help",               'h',            no_argument       },
    { "indent",             'i',            no_argument       },
    { "no-escape",          'e',            no_argument       },
    { "no-location",        CHAR_MAX + 7,   no_argument       },
    { "no-wrap",            CHAR_MAX + 2,   no_argument       },
    { "omit-header",        CHAR_MAX + 1,   no_argument       },
    { "output",             'o',            required_argument }, /* for backward compatibility */
    { "output-file",        'o',            required_argument },
    { "properties-input",   'P',            no_argument       },
    { "properties-output",  'p',            no_argument       },
    { "sort-by-file",       'F',            no_argument       },
    { "sort-output",        's',            no_argument       },
    { "strict",             CHAR_MAX + 8,   no_argument       },
    { "stringtable-input",  CHAR_MAX + 3,   no_argument       },
    { "stringtable-output", CHAR_MAX + 4,   no_argument       },
    { "style",              CHAR_MAX + 6,   required_argument },
    { "to-code",            't',            required_argument },
    { "unique",             'u',            no_argument       },
    { "version",            'V',            no_argument       },
    { "width",              'w',            required_argument },
    { "more-than",          '>',            required_argument },
    { "less-than",          '<',            required_argument },
  };
  END_ALLOW_OMITTING_FIELD_INITIALIZERS
  start_options (argc, argv, options, MOVE_OPTIONS_FIRST, 0);
  int optchar;
  while ((optchar = get_next_option ()) != -1)
    switch (optchar)
      {
      case '\0':                /* Long option with key == 0.  */
        break;

      case '>':
        {
          int value;
          char *endp;
          value = strtol (optarg, &endp, 10);
          if (endp != optarg)
            more_than = value;
        }
        break;

      case '<':
        {
          int value;
          char *endp;
          value = strtol (optarg, &endp, 10);
          if (endp != optarg)
            less_than = value;
        }
        break;

      case 'D':
        dir_list_append (optarg);
        break;

      case 'e':
        message_print_style_escape (false);
        break;

      case 'E':
        message_print_style_escape (true);
        break;

      case 'f':
        files_from = optarg;
        break;

      case 'F':
        sort_by_filepos = true;
        break;

      case 'h':
        do_help = true;
        break;

      case 'i':
        message_print_style_indent ();
        break;

      case 'n':            /* -n */
      case CHAR_MAX + 'n': /* --add-location[={full|yes|file|never|no}] */
        if (handle_filepos_comment_option (optarg))
          usage (EXIT_FAILURE);
        break;

      case 'o':
        output_file = optarg;
        break;

      case 'p':
        output_syntax = &output_format_properties;
        break;

      case 'P':
        input_syntax = &input_format_properties;
        break;

      case 's':
        sort_by_msgid = true;
        break;

      case CHAR_MAX + 8: /* --strict */
        message_print_style_uniforum ();
        break;

      case 't':
        to_code = optarg;
        break;

      case 'u':
        less_than = 2;
        break;

      case 'V':
        do_version = true;
        break;

      case 'w':
        {
          int value;
          char *endp;
          value = strtol (optarg, &endp, 10);
          if (endp != optarg)
            message_page_width_set (value);
        }
        break;

      case CHAR_MAX + 1:
        omit_header = true;
        break;

      case CHAR_MAX + 2: /* --no-wrap */
        message_page_width_ignore ();
        break;

      case CHAR_MAX + 3: /* --stringtable-input */
        input_syntax = &input_format_stringtable;
        break;

      case CHAR_MAX + 4: /* --stringtable-output */
        output_syntax = &output_format_stringtable;
        break;

      case CHAR_MAX + 5: /* --color */
        if (handle_color_option (optarg) || color_test_mode)
          usage (EXIT_FAILURE);
        break;

      case CHAR_MAX + 6: /* --style */
        handle_style_option (optarg);
        break;

      case CHAR_MAX + 7: /* --no-location */
        message_print_style_filepos (filepos_comment_none);
        break;

      default:
        usage (EXIT_FAILURE);
        /* NOTREACHED */
      }

  /* Version information requested.  */
  if (do_version)
    {
      printf ("%s (GNU %s) %s\n", last_component (program_name),
              PACKAGE, VERSION);
      /* xgettext: no-wrap */
      printf (_("Copyright (C) %s Free Software Foundation, Inc.\n\
License GPLv3+: GNU GPL version 3 or later <%s>\n\
This is free software: you are free to change and redistribute it.\n\
There is NO WARRANTY, to the extent permitted by law.\n\
"),
              "1995-2025", "https://gnu.org/licenses/gpl.html");
      printf (_("Written by %s.\n"), proper_name ("Peter Miller"));
      exit (EXIT_SUCCESS);
    }

  /* Help is requested.  */
  if (do_help)
    usage (EXIT_SUCCESS);

  /* Verify selected options.  */
  if (sort_by_msgid && sort_by_filepos)
    error (EXIT_FAILURE, 0, _("%s and %s are mutually exclusive"),
           "--sort-output", "--sort-by-file");

  /* Determine list of files we have to process.  */
  if (files_from != NULL)
    file_list = read_names_from_file (files_from);
  else
    file_list = string_list_alloc ();
  /* Append names from command line.  */
  for (cnt = optind; cnt < argc; ++cnt)
    string_list_append_unique (file_list, argv[cnt]);

  /* Test whether sufficient input files were given.  */
  if (file_list->nitems < 2)
    {
      error (EXIT_SUCCESS, 0, _("at least two files must be specified"));
      usage (EXIT_FAILURE);
    }

  /* Default the message selection criteria, and check them for sanity.  */
  if (more_than < 0)
    more_than = (less_than < 0 ? 1 : 0);
  if (less_than < 0)
    less_than = INT_MAX;
  if (more_than >= less_than || less_than < 2)
    error (EXIT_FAILURE, 0,
           _("impossible selection criteria specified (%d < n < %d)"),
           more_than, less_than);

  /* Read input files, then filter, convert and merge messages.  */
  allow_duplicates = true;
  msgcomm_mode = true;
  result = catenate_msgdomain_list (file_list, input_syntax, to_code);

  string_list_free (file_list);

  /* Sorting the list of messages.  */
  if (sort_by_filepos)
    msgdomain_list_sort_by_filepos (result);
  else if (sort_by_msgid)
    msgdomain_list_sort_by_msgid (result);

  /* Write the PO file.  */
  msgdomain_list_print (result, output_file, output_syntax,
                        textmode_xerror_handler, force_po, false);

  exit (error_message_count > 0 ? EXIT_FAILURE : EXIT_SUCCESS);
}


/* Display usage information and exit.  */
static void
usage (int status)
{
  if (status != EXIT_SUCCESS)
    fprintf (stderr, _("Try '%s --help' for more information.\n"),
             program_name);
  else
    {
      printf (_("\
Usage: %s [OPTION] [INPUTFILE]...\n\
"), program_name);
      printf ("\n");
      /* xgettext: no-wrap */
      printf (_("\
Find messages which are common to two or more of the specified PO files.\n\
By using the --more-than option, greater commonality may be requested\n\
before messages are printed.  Conversely, the --less-than option may be\n\
used to specify less commonality before messages are printed (i.e.\n\
--less-than=2 will only print the unique messages).  Translations,\n\
comments and extracted comments will be preserved, but only from the first\n\
PO file to define them.  File positions from all PO files will be\n\
cumulated.\n\
"));
      printf ("\n");
      printf (_("\
Mandatory arguments to long options are mandatory for short options too.\n"));
      printf ("\n");
      printf (_("\
Input file location:\n"));
      printf (_("\
  INPUTFILE ...               input files\n"));
      printf (_("\
  -f, --files-from=FILE       get list of input files from FILE\n"));
      printf (_("\
  -D, --directory=DIRECTORY   add DIRECTORY to list for input files search\n"));
      printf (_("\
If input file is -, standard input is read.\n"));
      printf ("\n");
      printf (_("\
Output file location:\n"));
      printf (_("\
  -o, --output-file=FILE      write output to specified file\n"));
      printf (_("\
The results are written to standard output if no output file is specified\n\
or if it is -.\n"));
      printf ("\n");
      printf (_("\
Message selection:\n"));
      printf (_("\
  -<, --less-than=NUMBER      print messages with less than this many\n\
                              definitions, defaults to infinite if not set\n"));
      printf (_("\
  ->, --more-than=NUMBER      print messages with more than this many\n\
                              definitions, defaults to 1 if not set\n"));
      printf (_("\
  -u, --unique                shorthand for --less-than=2, requests\n\
                              that only unique messages be printed\n"));
      printf ("\n");
      printf (_("\
Input file syntax:\n"));
      printf (_("\
  -P, --properties-input      input files are in Java .properties syntax\n"));
      printf (_("\
      --stringtable-input     input files are in NeXTstep/GNUstep .strings\n\
                              syntax\n"));
      printf ("\n");
      printf (_("\
Output details:\n"));
      printf (_("\
      --color                 use colors and other text attributes always\n\
      --color=WHEN            use colors and other text attributes if WHEN.\n\
                              WHEN may be 'always', 'never', 'auto', or 'html'.\n"));
      printf (_("\
      --style=STYLEFILE       specify CSS style rule file for --color\n"));
      printf (_("\
  -e, --no-escape             do not use C escapes in output (default)\n"));
      printf (_("\
  -E, --escape                use C escapes in output, no extended chars\n"));
      printf (_("\
      --force-po              write PO file even if empty\n"));
      printf (_("\
  -i, --indent                write the .po file using indented style\n"));
      printf (_("\
      --no-location           do not write '#: filename:line' lines\n"));
      printf (_("\
  -n, --add-location          generate '#: filename:line' lines (default)\n"));
      printf (_("\
      --strict                write out strict Uniforum conforming .po file\n"));
      printf (_("\
  -p, --properties-output     write out a Java .properties file\n"));
      printf (_("\
      --stringtable-output    write out a NeXTstep/GNUstep .strings file\n"));
      printf (_("\
  -w, --width=NUMBER          set output page width\n"));
      printf (_("\
      --no-wrap               do not break long message lines, longer than\n\
                              the output page width, into several lines\n"));
      printf (_("\
  -s, --sort-output           generate sorted output\n"));
      printf (_("\
  -F, --sort-by-file          sort output by file location\n"));
      printf (_("\
      --omit-header           don't write header with 'msgid \"\"' entry\n"));
      printf ("\n");
      printf (_("\
Informative output:\n"));
      printf (_("\
  -h, --help                  display this help and exit\n"));
      printf (_("\
  -V, --version               output version information and exit\n"));
      printf ("\n");
      /* TRANSLATORS: The first placeholder is the web address of the Savannah
         project of this package.  The second placeholder is the bug-reporting
         email address for this package.  Please add _another line_ saying
         "Report translation bugs to <...>\n" with the address for translation
         bugs (typically your translation team's web or email address).  */
      printf(_("\
Report bugs in the bug tracker at <%s>\n\
or by email to <%s>.\n"),
             "https://savannah.gnu.org/projects/gettext",
             "bug-gettext@gnu.org");
    }

  exit (status);
}
